Numerous disorders including hypertension, cardiac arrhythmias, and vascular headaches are treatable through biofeedback training reinforced by patient practice. In many cases, biofeedback training may be preferred to the use of drugs for treating specific disorders. INET proposes to develop an inexpensive, easily-used biofeedback trainer for clinic use and particularly for home practice. Features of the personal computer, including memory, graphics capabilities, educational and specialized software, would be utilized to develop a product superior to the current generation of outpatient biofeedback trainers. Under Phase I, INET will evaluate: features required for acceptance by clinicians; input modalities to satisfy treatment requirements; currently available biofeedback systems and input pickups; best-suited candidate personal computers and their available data acquisition systems; and feedback modalities shown best to facilitate learning. A result of Phase I will be the development of a functional specification from which the prototype system can be constructed, tested, and validated in Phase II; this will also include a preliminary conceptual design, including operations, display graphics, and cost data. Phase I work will determine the most productive applications of these techniques and the availability and requirements of hardware and software components.